Our efforts in the upcoming year will principally be concentrated towards two main objectives. The first, to produce pulmonary fibrosis in the hamster according to the technique recently reported by Snider et al. (Am Rev. Resp. Dis. 117, 289, 1978); then to evaluate the efficacy of D-penicillamine and beta-aminopropionitrile to prevent and/or reverse the lung fibrosis. The second is to continue the molecular basis of lung damage in response to paraquat and bleomycin at the cyclic nucleotide and prostaglandin levels.